diff --git a/src/test/ui/async-await/drop-order/drop-order-for-locals-when-cancelled.rs b/src/test/ui/async-await/drop-order/drop-order-for-locals-when-cancelled.rs new file mode 100644 index 00000000000..db396d3957e --- /dev/null +++ b/src/test/ui/async-await/drop-order/drop-order-for-locals-when-cancelled.rs @@ -0,0 +1,176 @@ +// aux-build:arc_wake.rs +// edition:2018 +// run-pass + +#![allow(unused_variables)] +#![deny(dead_code)] +#![feature(async_await)] + +// Test that the drop order for locals in a fn and async fn matches up. +extern crate arc_wake; + +use arc_wake::ArcWake; +use std::cell::RefCell; +use std::future::Future; +use std::marker::PhantomData; +use std::pin::Pin; +use std::rc::Rc; +use std::sync::Arc; +use std::task::{Context, Poll}; + +struct EmptyWaker; + +impl ArcWake for EmptyWaker { + fn wake(self: Arc) {} +} + +#[derive(Debug, Eq, PartialEq)] +enum DropOrder { + Function, + Val(&'static str), +} + +type DropOrderListPtr = Rc>>; + +struct D(&'static str, DropOrderListPtr); + +impl Drop for D { + fn drop(&mut self) { + self.1.borrow_mut().push(DropOrder::Val(self.0)); + } +} + +struct NeverReady; + +impl Future for NeverReady { + type Output = (); + fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll { + Poll::Pending + } +} + +async fn simple_variable_declaration_async(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); + NeverReady.await; +} + +fn simple_variable_declaration_sync(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); +} + +async fn varable_completely_contained_within_block_async(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + async { + let x = D("x", l.clone()); + } + .await; + let y = D("y", l.clone()); + NeverReady.await; +} + +fn varable_completely_contained_within_block_sync(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + { + let x = D("x", l.clone()); + } + let y = D("y", l.clone()); +} + +async fn variables_moved_into_separate_blocks_async(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); + async move { x }.await; + async move { y }.await; + NeverReady.await; +} + +fn variables_moved_into_separate_blocks_sync(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); + { + x + }; + { + y + }; +} + +async fn variables_moved_into_same_block_async(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); + async move { + x; + y; + }; + NeverReady.await; +} + +fn variables_moved_into_same_block_sync(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); + { + x; + y; + }; + return; +} + +async fn move_after_current_await_doesnt_affect_order(l: DropOrderListPtr) { + l.borrow_mut().push(DropOrder::Function); + let x = D("x", l.clone()); + let y = D("y", l.clone()); + NeverReady.await; + async move { + x; + y; + }; +} + +fn assert_drop_order_after_cancel>( + f: impl FnOnce(DropOrderListPtr) -> Fut, + g: impl FnOnce(DropOrderListPtr), +) { + let empty = Arc::new(EmptyWaker); + let waker = ArcWake::into_waker(empty); + let mut cx = Context::from_waker(&waker); + + let actual_order = Rc::new(RefCell::new(Vec::new())); + let mut fut = Box::pin(f(actual_order.clone())); + let _ = fut.as_mut().poll(&mut cx); + drop(fut); + + let expected_order = Rc::new(RefCell::new(Vec::new())); + g(expected_order.clone()); + assert_eq!(*actual_order.borrow(), *expected_order.borrow()); +} + +fn main() { + assert_drop_order_after_cancel( + simple_variable_declaration_async, + simple_variable_declaration_sync, + ); + assert_drop_order_after_cancel( + varable_completely_contained_within_block_async, + varable_completely_contained_within_block_sync, + ); + assert_drop_order_after_cancel( + variables_moved_into_separate_blocks_async, + variables_moved_into_separate_blocks_sync, + ); + assert_drop_order_after_cancel( + variables_moved_into_same_block_async, + variables_moved_into_same_block_sync, + ); + assert_drop_order_after_cancel( + move_after_current_await_doesnt_affect_order, + simple_variable_declaration_sync, + ); +}